Sliabh na Caillí (Mountain of the Hag), also known as Lough crew, is a infamous passage tomb is one of the four main passage tombs in Ireland next to Brú na Bóinne, Carrowkeel and Carrowmore dating to roughly 3,300 BCE. The site consists of cruciform chambers covered by a mound structure. Within, and on the outside of kerbstones are a unique style of megalithic petroglyphs including circles, spirals, lozenge shapes, leaf shapes, radiating lines. Site has three parts – two of which are on hill tops, Carnbane East and Carnbane West, and the less preserved Patrickstown. Mythology states that it was created by a giant hag who while striding across the land, dropped her cargo of large stones from her apron as she was traveling to her home at Slieve Gullion. Local green gritstone is soft enough to carve making up the orthostats and structural stones of the monuments. In 1980, the archaeologist Martin Brennan discovered that Cairn T in Carnbane East was constructed to receive the rising sun on the Spring and Autumnal Equinoxes, shining down the passage and illuminating the rock art on the back stone. There are also alignments between Cairn L at Lough Crew, Knowth, and Dowth.